In recent years, there has been known a fuel cell vehicle which supplies electric power generated by a fuel cell system to a motor and drives wheels by this motor. For example, Japanese Patent Laid-Open No. 2001-130468 (FIG. 1) discloses a fuel cell system providing electric power generation in a fuel cell stack by a chemical reaction between hydrogen as fuel gas and oxygen as reactive gas. Here, oxygen is taken in from the air through an air compressor, and hydrogen is supplied from a fuel cylinder through a flow regulating valve.
For the purpose of extending mileage for one fuel gas supply, and the like, the fuel cylinder mounted on the fuel cell vehicle is filled with high-pressure hydrogen gas. In the fuel cylinder filled with the high-pressure hydrogen gas, besides the flow regulating valve, a pressure control valve is provided to prevent an internal gas pressure from being a certain gas pressure or more.
When the pressure control valve is actuated to discharge the hydrogen gas from the fuel cylinder to the air, it is preferable that the hydrogen gas is discharged to the air, in other words, to the outside of the vehicle while the discharge pressure is lowered and the fuel gas is diffused.
However, in the above-described document related to the prior art, there is no description as to how to discharge the hydrogen gas by use of the pressure control valve itself and by operation thereof.
The present invention was made in consideration for the foregoing problem. It is an object of the present invention to provide a fuel cell vehicle on which a fuel cylinder is mounted, which is capable of efficiently diffusing fuel gas discharged to the air from the fuel cylinder and discharging the fuel gas to the outside of the vehicle.